Kyra and Kira are definitely pronounced like Keera. However, I'd stay away from Kyria (that looks like Keer ee a) and Kiera. In this day and age, at least in the USA, Kiera would probably be pronounced like Kee-AIR-a like Sierra with a K. There will be the few that pronounce Kyra like KYE-ra, but I think you run the risk of mispronounciation with just about any more unusual name. I think Kira is the most fool proof spelling.